This video tutorial from IDModeling demonstrates how to display a ground model and your network in a 3D view using Wallinford Software's InfoWorks. This is a great way to quickly identify inaccurate invert elevations, missing data, and other data anomalies.
HEC-RAS ia a free Hydraulic Modeling and Analysis Software Developed and Distributed by US Army Corps of Engineers. This is a really useful tool for Hydraulic Analysis and Flood Plain Mapping. Link: http://www.hec.usace.army.mil/
Penn State Public Broadcasting is developing the Geospatial Revolution Project, an integrated public media and outreach initiative about the world of digital mapping and how it is changing the way we think, behave, and interact.